As known, bicycles used in greatly-varying riding conditions, like mountain bikes or trekking bikes, are formed from a rear frame rotatably connected to a main frame, called front triangle, and a damper is arranged between them that limits the oscillations thereof.
In particular, the damper is hinged to the main frame and to an end of a rock-er link (also called Rocker Link), which is in turn hinged to the rear frame at an opposite end and to the main frame at an intermediate hinging point be-tween the two opposite ends. In the different riding conditions, which range from steep downhill slopes to steep uphill slopes, the distribution of the load between the front wheel and the rear wheel changes drastically. When the bicycle is ridden on flat terrain, roughly 70% of the weight force acts on the rear wheel and only 30% acts on the front wheel. On the other hand, when riding uphill, almost 100% of the weight acts on the rear wheel and when riding downhill it may be that almost 100% of the weight is supported by the front wheel.
With bicycles, like mountain bikes, which foresee the damper for damping the movement of the rear frame with respect to the main frame, there is a need to vary the rigidity of the damper and/or the geometry of the bicycle frame as a function of the terrain to be traveled on with the bicycle itself, i.e. as a function of whether the bicycle must travel on flat, uphill or downhill terrain.
An example of such bicycle frames is shown in document US 2014/0159338.
A purpose of the present invention is to satisfy such requirements of the prior art, in a simple, rational and advantageous solution.
Such purposes are accomplished by the characteristics of the invention given in the independent claim. The dependent claims outline preferred and/or particularly advantageous aspects of the invention.